Scarifier and moss rake adapted to be fitted to a small power driven cultivator

ABSTRACT

A power operated hand guided device is designed to scarify, edge, and aerate lawns and grass. It comprises tools in the form of blades (26) which rotate in a vertical plane about the common axis of a pair of tool-holder shafts. Each tool holder shaft (21) is rotatably connected to a bearing (12) supported on a vertically adjustable beam (23) having wheels (24 and 25) or rollers at each end. A brake (37) which retards the forward movement by friction with the ground is connected to the motor assembly by a rod (38).

BACKGROUND OF THE INVENTION

The present invention is concerned with the field of mechanized gardencultivation and its object is a scarifier, moss rake and lawn or grassaerator device.

Various small devices are known which are intended mainly for lawnmaintenance and which carry tools in the form of blades rotating in avertical plane and disposed along a motor driven shaft. A first type ofdevice comprises a frame in the form of a box open at its bottom faceand supporting a motor on its top face, which forms a cover; one or moreshafts supporting the blades is or are disposed inside the box; thisshaft is in turn supported by bearings on the box and is driven by themotor with the aid of a chain drive, for example; the box is providedwith side wheels or rollers. In a device of this kind the depth of cutis adjustable by regulating either the height of the shaft relative tothe wheels or the height of the wheels relative to the box. Devices ofthis kind are practical, but they have the disadvantage of beingdedicated to one particular type of work.

Small devices of the motorized rake type are also known, in which thedrive half-shafts project at the side of a motor casing and are adaptedto receive either wheels, when the device is to be used as tractionmeans, or rotary tools. To enable the device to be used as a scarifier,equipments have thus been proposed which consist of a pair of shaftsadapted to be connected by sleeve couplings to the drive half-shafts atone end, while their other end is provided with a wheel hub and a wheeladapted to turn freely about the hub; each shaft carries a plurality ofscarifier blades; the coupled end is fastened to the drive half-shaft bymeans of a pin; the rotation of the motor rotates the blades, while therotation of the wheels, that is to say the propulsion of the device, isdependent solely on the operator. The advantage of a device of this kindis its ability to be used for various types of work, but a disadvantageis that the depth of cut into the ground is dependent on the diameter ofthe wheels, and is therefore not adjustable for a given equipment.

For more precise information regarding the prior art reference may bemade to the following publications: U.S.-A-No. 4,483,400 (ARNDT),U.S.-A-No. 3,127,940 (HUTCHINSON), U.S.-A-No. 2,794,308 (CAVANAUG),FR-A-1,376,521 (BRIBAN) and FR-A-690,298 (KOROUM).

SUMMARY

The present invention relates to a device for equipping small mechanizedcultivation motors, which is of the second type described above andwhich is detachable in order to permit the multipurpose use of the motorand enables the depth of cut to be adjusted.

According to the present invention, a cultivation device of theso-called "scarifier" type cuts into the ground with the aid of tools inthe form of blades rotating in a vertical plane about the common axis ofa pair of tool carrier shafts. Each of these shafts is supported at afirst end by a drive half-shaft of a small drive unit of the "motorizedhoe" type and is connected to free rotation to a bearing supported by alongitudinal member equipped with wheels or rollers at each end.

The device preferably incorporates means for the adjustment of theheight of said bearing above the longitudinal member, in such a memberas to regulate the depth of cut into the ground. Despite thisadjustability of the depth of cut, the longitudinal members areconnected together only by means of the tool carrier shafts.

In a preferred form of construction of the device according to theinvention the connection between the bearing and the longitudinal memberis made by a pair of slides fastened to the bearing and provided withcavities whose axes are substantially vertical, and by a pair of pillarsfastened to the longitudinal members and shaped to slide in said slides.In this embodiment at least one of the slides and the correspondingpillar are provided with means for securing them in their relativepositions. The securing means enables the adjustment of the height ofthe bearing above the longitudinal members.

In a particularly simple form of construction of the securing means, apair of holes are formed along the slide for the passage of a pin, and aplurality of similar holes are formed in the pillar. The distance h1separating the holes in the slide is equal to three times half thedistance h2 separating the holes in the pillar (h1= 3·h2/2 ).

According to an advantageous constructional feature the relationship offree rotation between each tool carrier shaft and the correspondingbearing is achieved by means of a second half-shaft engaged in thebearing. The relationship between said second half-shaft and the bearingis fixed in the axial direction with the aid of an end washer and asleeve supported on the half-shaft. The second half shaft is rotatablein the bearing with the aid of an antifriction ring disposed between thehalf-shaft and the bearing.

According to another constructional arrangement the longitudinal memberhas a first steplike offset in the horizontal plane adjacent its fronthalf, as the result of which the front wheel can be disposed at the sideof the longitudinal member, and a second steplike offset in the verticalplane adjacent its rear half as the result of which the rear wheel canbe disposed under the longitudinal member. The connection between therear wheel and the longitudinal member is advantageously made by a forkmounted on the longitudinal member to pivot about a vertical axis.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood and details relatingthereto will engage from the description given below with reference tothe accompanying drawings, in which:

FIGS. 1 and 1a illustrate schematically a first type of device of theprior art,

FIGS. 2 and 2a similarly illustrate a device of the second type of theprior art, while FIGS. 3 and 3a illustrate in comparable manner theprinciple of the device according to the invention,

FIG. 4 is a partial exploded view in perspective of one form ofconstruction of said device,

FIG. 5 is a partial elevation of the device on a larger scale,

FIG. 6 is a top plan view of the device illustrated in FIG. 5,

FIG. 7 is a partial sectional view taken along the line A in FIG. 5,

FIG. 8 is a side elevational view of a device in accordance with anotherillustrative embodiment of the invention,

FIG. 9 is a side elevational view of a horizontal arm utilized in theembodiment of FIG. 8,

FIG. 10 is a vertical sectional view of the horizontal arm illustratedin FIG. 9, together with certain associated parts, and

FIG. 11 is a top plan view of the device of FIG. 8, with certaincomponents shown in section.

DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

In FIGS. 1 and 1a a specialized type of scarifier of the prior artcomprises a box frame 1 equipped with side wheels 2 and containing inits interior a scarifier blade carrier shaft driven by a motor unit 4;transmission means 5 transmit the rotary motion from the motor to theshaft; a device of this kind is provided with means for adjusting theheight of the shaft 3 above the ground; it will be observed that thewheels 2 are independent of the shaft 3.

In all the drawings the arrows 6 indicate adjustability of height andthe arrows 7 the direction of advance.

In FIGS. 2 and 2a, in another device of the prior art, half-shafts suchas 10 project from a motor casing 11 and are fastened to blade carrierhalf-shafts, such as 12. The outer end of each half-shaft 12 is shapedas a hub 13, on which is mounted a wheel 14 which is free to turn aboutthe hub. In contrast to the preceding case, the wheels are connected tothe blade carrier shafts even if they are free to rotate relative tothese shafts. In this case the depth of the cuts made in the ground bythe blades is determined by the difference between the diameter of thewheels and that of the blades. It will be noted that the device shown inFIG. 2 is not restricted to scarification since the shafts 12 can bereplaced with driven wheels for example, with hoe blades, or with otherrotating implements.

It will be recalled that the invention proposes an equipment adapted tobe fitted to a drive unit, as is the equipment shown in FIGS. 2 and 2a,but one which in addition has the advantage of adjustability in height,as in the case of the device shown in FIG. 1.

In FIGS. 3, 3a and 4 a scarifier equipment comprises a pair of toolcarrier shafts 21 which are each connected at a first end by a sleevecoupling adjacent drive half-shaft 20 and at their second end to abearing 22 supported by a longitudinal member 23 provided at its frontand rear ends with respective wheels 24, 25. It will be observed that anequipment of this type is adapted to be fitted to the same drive unit 11as the equipment shown in FIGS. 2 and 2a. However, the depth of cut nolonger depends on the difference between the diameters of the wheels, onthe one hand, and the blades on the other hand, but it is determined bythe height of the bearing above the longitudinal member.

In FIG. 4 it can more particularly be seen that the connection betweenthe bearing 22 and the longitudinal member 23 is made with the aid of apair of slides 31, 32 fastened to the bearing; these slides havecavities whose axes are vertical and through which pass respectivepillars 34 and 33 fastened at their bases to the longitudinal member 23.

The shaft 21 carrying a plurality of blades 26 is hollow in order to beable to receive, at a first end, the drive half-shaft 20 and, at itssecond end, a second half-shaft 27 extending into the bearing 22.Correspondingly disposed holes for pins enable the shaft 21 to be madefast to the half-shafts 20 and 27. It should be understood that FIG. 4shows only half of an equipment. In addition it will be seen that thisfigure that to the rear of the drive unit 11 a brake spur 37 is providedwhich is intended to slow down forward movement by rubbing against theground, this spur of substantially semicircular shape being connected tothe drive unit by a rod 38 of adjustable length.

In FIGS. 5 and 7, which show only half of an equipment and which omitthe drive unit, the shape of the longitudinal member 23 will be moreparticularly observed. The member 23 has two steplike offsets, whichterm is intended to mean a shape in which the member is bent over in aplane, once in one direction and once in the opposite direction, so thatthe rectilinear parts of the member are no longer in alignment, whilestill being parallel. A first such offset 41 in the horizontal planeenables the front wheel 44 to be accommodated in such a manner that thecenter plane of said wheel coincides with the center plane of the otherpart of the longitudinal member (FIG. 6), while a second such offset 42in the vertical plane enables the rear wheel 45 to be disposed under thelongitudinal member and to be freely pivotable as shown by the dot-dashline 46 about a vertical axis 47. The rear wheel 45 is held in a fork 48mounted for pivoting about the axis 47. In figure the means foradjustment of the height of the blades 26 relative to the ground will beparticularly observed; the slide 31 is provided with two holes 49 lyinga distance h1 apart, while the pillar 33 has a plurality of similarholes, such as 50, lying a distance h2 apart, h1 being equal to 3·h2/2.

As shown in FIG. 7 the half-shaft 27 is located at its outer end in thebearing 60, which for example is annular, and include an annularantifriction ring 61 of antifriction metal. Instead of the antifrictionring a rolling contact bearing may be employed, although this may not bejustified for the small forces or low speeds involved. The half-shaft 27is secured from movement along the axis 63 by an end washer 64 on oneside of the bearing 60, and by a sleeve 65 bearing against the bladecarrier shaft 21 on the other side. The tubular structure of the shaft21 enables it to be sleeved around the half-shafts 20 and 27, to whichit is fastened in respect of both rotation and translation by pins whichare not shown in the drawings but which pass through holes 66 and 67respectively.

While the adjustment of the height above the ground in the device shownin FIGS. 4 to 7 is achieved by sliding translatory movement of thebearing 22 relative to the longitudinal member 23, a method of heightadjustment by rotation will now be described.

In FIGS. 8 to 11 a device according to a second embodiment of theinvention comprises, like the device described above, a pair of wheels94 and 95 mounted on a longitudinal member 93, which in this case isrectilinear and fastened to a side plate 69. The device also comprisestwo hollow shafts 91 equipped with scarifier blades 96 and intended toreceive half-shafts 97; as previously, the shafts 91 are mounted forrotation in bearings 92. However, in contrast to the device describedabove, the bearings 92 are here not fastened to vertical slides, buteach of them is fastened to a horizontal arm 70 supporting a horizontalhalf-shaft 71. The longitudinal member 93 in turn supports a horizontalsleeve 72 intended to receive the half-shaft 71. The half-shaft 71 andthe sleeve 72 are fastened one in the other by a nut 73 preventing theirtranslatory movement relative to each other but allowing their rotation.

A bent lever 74 provided with an operating handle 75 is pivotallymounted on the half-shaft 71 and is fixed for rotation with the arm 70by means of a fork 76. As a result, the pivoting of the handle as shownby arrow 77 entails an identical pivoting (arrow 78) of the arm 70 andconsequently a variation of the height, relative to the ground, of thehollow shaft 91, the scarifier blades and the drive unit (not shown inthese figures).

The bent lever 74 is pressed against the arm 70 by a spring 79. Becauseof the fork 76 and of sufficient clearance around the sleeve 72, thelever 74 can pivot transversely (arrow 80); as the result of thispivoting and with the aid of a pin 81 adapted to snap into one of theapertures 82 in the plate 69, the scarifier blades can be fixed atcertain heights 83 above the ground. This second embodiment has theadvantage of being simpler to assemble than the previous one.

Although particular embodiments of the invention have been described andillustrated, it must be understood that the scope of the invention isnot limited to these embodiments, but that it extends to anyagricultural device having the general characteristics indicated above;in particular it extends to devices other than scarifiers which haverotating blades serving a different purpose from that described andrequiring height adjustment for their optimum utilization.

I claim:
 1. A cultivation device having ground cutting tools arrangedfor rotation in vertical planes about a common axis, the devicecomprising, in combination:a drive unit including a pair of drivehalf-shafts coaxially extending from opposite sides thereof; a pair oftool carrier shafts extending outwardly from the respective drivehalf-shafts; two bearing members mounted adjacent the respective outerends of the tool carrier shafts, the tool carrier shafts being freelyrotatable with respect to their corresponding bearing members; aplurality of longitudinal members extending in directions traverse tosaid common axis for respectively supporting said bearing members, saidlongitudinal members are connected together only by means of saidbearing members, said tool carrier shafts and said drive half-shafts;wheel means rotatably carried adjacent each end of each of saidlongitudinal members; and means for adjustably connecting each of saidbearing members to its supporting longitudinal member, to thereby permitadjustment of the depth of cut into the ground of said cutting tools. 2.A cultivation device having ground cutting tools arranged for rotationin vertical planes about a common axis, the device comprising, incombination:a drive unit including a pair of drive half-shafts coaxiallyextending from opposite sides thereof; a pair of tool carrier shaftsextending outwardly from the respective drive half-shafts; two bearingmembers mounted adjacent the respective outer ends of the tool carriershafts, the tool carrier shafts being freely rotatable with respect totheir corresponding bearing members; a plurality of longitudinal membersextending in directions transverse to said common axis for respectivelysupporting said bearing members; wheel means rotatably carried adjacenteach end of each of said longitudinal members; and means for adjustableconnecting each of said bearing members to its supporting longitudinalmember, in which the adjustable connecting means for each bearing membercomprises a pair of slide members fastened to the bearing member andhaving vertically extending openings therein, a pair of pillars slidablydisposed in the openings in the respective slide members and means forreleasably securing the slide members to their corresponding pillars, tothereby permit adjustment of the depth of cut into the ground of saidcutting tools.
 3. A cultivation device as defined by claim 2, said slidemembers and said pillars each including a plurality of spaced holes, thespacing between the holes in the slide members being three timesone-half the spacing between the holes in the pillars.
 4. A cultivationdevice having ground cutting tools arranged for rotation in verticalplanes about a common axis, the device comprising, in combination:adrive unit including a pair of drive half-shafts coaxially extendingfrom opposite sides thereof; a pair of tool carrier shafts extendingoutwardly from the respective drive half-shafts; two bearing membersmounted adjacent the respective outer ends of the tool carrier shafts,the tool carrier shafts being freely rotatable with respect to theircorresponding bearing members; a plurality of longitudinal membersextending in directions transverse to said common axis for respectivelysupporting said bearing members; wheel means rotatably carried adjacenteach end of each of said longitudinal members; and means for adjustableconnecting each of said bearing members to its supporting longitudinalmember, to thereby permit adjustment of the depth of cut into the groundof said cutting tools, wherein the means for adjustable connecting eachbearing member to its supporting longitudinal member comprises an armfastened adjacent one to its ends to the bearing member, a sleevefastened to the longitudinal member, and an interconnecting shaftdisposed within said sleeve and fastened adjacent the other end of thebearing member.
 5. A cultivation device as defined by claim 4, whichfurther comprises a side plate mounted on one of said longitudinalmembers and having a plurality of apertures therein; a lever connectedto said arm and extending therefrom in juxtaposition with said sideplate; and pin means carried by said lever in position to be received bysaid apertures, whereby movement of said lever pivots said arm to adjustthe depth of cut into the ground of said cutting tools.